xxgary81xx

I had a pioneer bluetooth & stereo unit installed 2yrs ago at Best Buy. I recently had a CEL come on with the code U0164 lost communication with unified meter & a/c amp or combination meter. I had autozone reset the light and it came back on 10 min later. I ended up going to nissan today and they simply said its a code that really means nothing and they will reset it. They blame the aftermarket stereo for setting off the CEL. They said I will have to live with the light, if I keep the stereo in. I went to a buddy that has a shop and he went ahead a disconnected the battery for 15 min which I hoped would do the trick, of course it came back on. I am going back to best buy tomorrow and see if they can find anything wrong. At this point i pretty much have to live with the CEL or go back to stock stereo unit. Does anyone know if its possible for something like this to happen 2 yrs after install, or is this dealership ********. I really dont want to drive with a CEL on, im worried one day something will go wrong and I will assume its the U0164 code. Any suggestions on what to do would definitely be appreciated. I spent alot of money on the unit and its great...